Hi all :)(adsbygoogle = window.adsbygoogle || []).push({});

Hope the day has been good to you....i am stuck on a question for my uni assignment, and have been stuck on this one for about 3 days to no avail....i don't even know where to start. I'm not too sure whether i need a certain equation for the question or if i have to come up with one using the information in the question...

If anyone could please help me through it would be greatly appreciated as i've only got 4 days left.....if not thanks for looking anyways :)

There once was a planet - quite far

In orbit around a star

The star’s mass was ms

The planet’s mass you assess

Using the orbital radii, r

You can assume the radius of the planet’s and the star’s circular orbits around the

centre of mass of the system are r_{p}= 1.5 × 10^{8}km and r_{s}= 1.0 × 10^{6}km, respectively, with

m_{s}= 2.0 × 10^{30}kg.

Calculate the mass of the planet, m_{p}, showing all your workings and giving your answer in scientific notation to the appropriate number of significant figures.

Any help would be amazing as i'm at my wits end !

Many Thanks,

Ax

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# Mass of a planet

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